Update tests to use .NET 6 (#2674)

Src/Newtonsoft.Json.TestConsole/Newtonsoft.Json.TestConsole.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFrameworks>net46;net5.0</TargetFrameworks>
+    <TargetFrameworks>net46;net6.0</TargetFrameworks>
     <LangVersion>latest</LangVersion>
     <RootNamespace>Newtonsoft.Json.TestConsole</RootNamespace>
     <AssemblyName>Newtonsoft.Json.TestConsole</AssemblyName>

Src/Newtonsoft.Json.Tests/Newtonsoft.Json.Tests.csproj

@@ -1,6 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFrameworks Condition="'$(TestFrameworks)'==''">net46;net40;net35;net20;net5.0;netcoreapp3.1;netcoreapp2.1</TargetFrameworks>
+    <TargetFrameworks Condition="'$(TestFrameworks)'==''">net46;net40;net35;net20;net6.0;netcoreapp3.1;netcoreapp2.1</TargetFrameworks>
     <TargetFrameworks Condition="'$(TestFrameworks)'!=''">$(TestFrameworks)</TargetFrameworks>
     <LangVersion>9.0</LangVersion>
     <VersionPrefix>1.0</VersionPrefix>
@@ -109,7 +109,7 @@
     <DefineConstants>NET20;$(AdditionalConstants)</DefineConstants>
   </PropertyGroup>
 
-  <ItemGroup Condition="'$(TargetFramework)'=='net5.0'">
+  <ItemGroup Condition="'$(TargetFramework)'=='net6.0'">
     <PackageReference Include="BenchmarkDotNet" Version="$(BenchmarkDotNetPackageVersion)" />
     <PackageReference Include="FSharp.Core" Version="$(FSharpCorePackageVersion)" />
     <PackageReference Include="System.ObjectModel" Version="$(SystemObjectModelPackageVersion)" />
@@ -124,7 +124,7 @@
     <PackageReference Include="xunit.runner.visualstudio" Version="$(XunitRunnerVisualStudioPackageVersion)" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="$(MicrosoftNETTestSdkPackageVersion)" />
   </ItemGroup>
-  <PropertyGroup Condition="'$(TargetFramework)'=='net5.0'">
+  <PropertyGroup Condition="'$(TargetFramework)'=='net6.0'">
     <AssemblyTitle>Json.NET Tests .NET Standard 2.0</AssemblyTitle>
     <ReferringTargetFrameworkForProjectReferences>.NETStandard,Version=v2.0</ReferringTargetFrameworkForProjectReferences>
     <DefineConstants>NETSTANDARD2_0;DNXCORE50;PORTABLE;HAVE_BENCHMARKS;HAVE_REGEX_TIMEOUTS;$(AdditionalConstants)</DefineConstants>

Src/Newtonsoft.Json.Tests/Utilities/ExpressionReflectionDelegateFactoryTests.cs

@@ -145,7 +145,8 @@ namespace Newtonsoft.Json.Tests.Utilities
                 }, new[]
                 {
                     "Cannot create an abstract class.",
-                    "Cannot create an abstract class 'System.Type'." // mono
+                    "Cannot create an abstract class 'System.Type'.", // mono
+                    "Cannot dynamically create an instance of type 'System.Type'. Reason: Cannot create an abstract class." // net60
                 });
         }
 

Src/global.json

@@ -1,5 +1,5 @@
 {
   "sdk": {
-    "version": "6.0.100"
+    "version": "6.0.300"
   }
 }